body, ul {
  padding: 0;
  margin: 0;
}
ul {
  list-style-type: none;
  position: relative;
}
.my-menu {
  background-color: #000;
  padding: 0 8px;
}
.my-menu-item {
  color: #ddd;
  display: inline-block;
  height: 60px;
  line-height: 60px;
  padding: 0 5px;
  cursor: pointer;
  white-space: nowrap;
}
.my-menu-item:hover {
  color: #fff;
}

.my-menu-select {
  position: absolute;
  top: 0;
  left: 20px;
  display: block;
  width: 0;
  height: 5px;
  background-color: green;
  transition: all .5s;
}
